Siengsanan Jarunee, Chaichoune Kridsada, Phonaknguen Rassameepen, Sariya Ladawan, Prompiram Phirom, Kocharin Waraporn, Tangsudjai Sririporn, Suwanpukdee Sarin, Wiriyarat Witthawat, Pattanarangsan Rattapan, Robertson Ian, Blacksell Stuart D, Ratanakorn Parntep
The Monitoring and Surveillance Center for Zoonotic Diseases in Wildlife and Exotic Animals, Faculty of Veterinary Science, Mahidol University, Nakhon Pathom, Thailand.
J Wildl Dis. 2009 Jul;45(3):740-7. doi: 10.7589/0090-3558-45.3.740.
Wild bird surveillance for highly pathogenic avian influenza (HPAI) H5N1 virus from 2004 to 2007 in Thailand indicated that the prevalence of infection with avian influenza H5N1 virus in wild birds was low (1.0%, 95% confidence interval [CI]: 0.7-1.2, 60/6,263 pooled samples). However, the annual prevalence varied considerably over this period, with a peak of 2.7% (95% CI: 1.4, 4.1) in 2004. Prevalence dropped to 0.5% (95% CI: 0.3, 0.8]) and 0.6% (95% CI: 0.3, 1.0) in 2005 and 2006, respectively, and then increased to 1.8% (95% CI: 1.0, 2.6) in 2007. During this period, 16 species from 12 families of wild birds tested positive for H5N1 virus infection. All samples from juvenile birds were negative for H5N1 virus, whereas 0.6% (95% CI: 0.4, 0.9) of pooled samples from adult birds were positive. Most positive samples originated from peridomestic resident species. Infected wild bird samples were only found in provinces where poultry outbreaks had occurred. Detection of H5N1 virus infection in wild birds was reported up to 3 yr after eradication of the poultry outbreaks in those provinces. As observed with outbreaks in poultry, the frequencies of H5N1 outbreaks in wild birds were significantly higher in winter. Further understanding of the mechanisms of persistence and ongoing HPAI H5N1 transmission between wild birds and domestic poultry is needed.
2004年至2007年泰国对野生鸟类进行的高致病性禽流感（HPAI）H5N1病毒监测表明，野生鸟类感染H5N1禽流感病毒的患病率较低（1.0%，95%置信区间[CI]：0.7 - 1.2，60/6263份合并样本）。然而，在此期间年患病率变化很大，2004年达到峰值2.7%（95% CI：1.4，4.1）。2005年和2006年患病率分别降至0.5%（95% CI：0.3，0.8）和0.6%（95% CI：0.3，1.0），然后在2007年升至1.8%（95% CI：1.0，2.6）。在此期间，12个野生鸟类科的16个物种检测出H5N1病毒感染呈阳性。所有幼鸟样本的H5N1病毒检测均为阴性，而成鸟合并样本中有0.6%（95% CI：0.4，0.9）呈阳性。大多数阳性样本来自家域周边的常住物种。仅在发生家禽疫情的省份发现了感染H5N1病毒的野生鸟类样本。在那些省份根除家禽疫情后长达3年仍报告检测到野生鸟类感染H5N1病毒。正如在家禽疫情中所观察到的，野生鸟类中H5N1疫情的发生频率在冬季显著更高。需要进一步了解HPAI H5N1病毒在野生鸟类和家禽之间持续存在及传播的机制。
